The main research interest in Open Source Software (OSS) has been in answering the questions of why individuals and organizations without economic compensation contribute to OSS projects and how these projects are organized. In this paper we instead focus on managerial decisions for acquisition of OSS and discuss potential barriers for widespread use of OSS. Based on existing literature and a small case study, we develop and discuss the hypothesis that a major barrier may be the "customer" organizations’ uncertainty and unfamiliarity with the relationships with OSS "vendors". To develop viable models for these relationships is an important challenge, which we will deal with in a research project, of which this paper should be seen as a first step.